I have a 112 gallon tank and have a current pH of 8.4. For the Tiger Oscars and convict cichlids that I am going to be putting in tank, could I lower the pH (more acidic) with vinegar? If so how much?
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How to lower pH level in tank
- Thread starter Hank82
- Start date
Tbh I would personally pass on the Oscar the Convict will be ok. Adding anything to lower or raise the PH can be risky.
As mentioned, there are some SA cichlids (and a number of CA cichlids) that come from harder water, Andinoacara rivulatus and stalsbergi are two obvious examples, and yes,
duanes
is familiar with a number of harder water cichlids.
I did black water tanks at one time, which meant lowering pH in my location at the time. There are ways to do it, it takes some tinkering and monitoring to get it right so it's stable, but it can be done. I did it years ago and back then I added acids and extracts directly to the water. I was successful, but a better way to go imo, and what I'd do now, is peat moss-- not hard to find info on this online. Still takes some tinkering to get the right amount for your tank and water and target pH level, but you're not adding stuff to the tank all the time. Another way is get an RO unit and include RO water with water changes, which again, takes some tinkering to work out.
It's why a lot of people will say don't bother and just get cichlids to suit your water, but in reality it can be done. I believe
ryansmith83
has done it to get his Heros severus to breed successfully.
duanes
is familiar with a number of harder water cichlids.I did black water tanks at one time, which meant lowering pH in my location at the time. There are ways to do it, it takes some tinkering and monitoring to get it right so it's stable, but it can be done. I did it years ago and back then I added acids and extracts directly to the water. I was successful, but a better way to go imo, and what I'd do now, is peat moss-- not hard to find info on this online. Still takes some tinkering to get the right amount for your tank and water and target pH level, but you're not adding stuff to the tank all the time. Another way is get an RO unit and include RO water with water changes, which again, takes some tinkering to work out.
It's why a lot of people will say don't bother and just get cichlids to suit your water, but in reality it can be done. I believe
ryansmith83
has done it to get his Heros severus to breed successfully.
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...Just to add a bit-- the reason lowering pH to a stable target value can take some tinkering and monitoring to work out is that, besides pH, you're dealing with alkalinity, technically not the same. pH essentially measures hydrogen ions (acid) in the water, alkalinity relates to carbonate/bicarbonate in the water, or "buffering" capacity. Alkalinity acts like a sponge, you can add acids and, in effect, it 'buffers' pH by absorbing them, keeping pH stable. This 'sponge' can become full, so it can't take on anymore acid, which is when you can have a pH crash. Sufficient buffering prevents this.
Therefore, lowering pH and keeping it stable, so it doesn't go right back up or doesn't go too low, can be something of a balancing act to work out and more fussing than if your water just stays at it's natural pH on its own, or does so without any fuss by simply adding something like baking soda or a commercial 'buffer'. A lot of people prefer to avoid any extra fussing with chemistry and just keep fish that suit their local water.
Therefore, lowering pH and keeping it stable, so it doesn't go right back up or doesn't go too low, can be something of a balancing act to work out and more fussing than if your water just stays at it's natural pH on its own, or does so without any fuss by simply adding something like baking soda or a commercial 'buffer'. A lot of people prefer to avoid any extra fussing with chemistry and just keep fish that suit their local water.
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I agree with the others, and consider oscars a less than an ideal choice for constant pH 8+ water.
Any Central American (like convicts) and Mexican cichlids do well in a pH of 8.4, as would some cichlids from west of the Andes in South America, or all rift lake Africans.
In my experience coming from a place with relatively high tap water pH myself, Oscars usually end up with chronic diseases like HLLE in high pH water, unless tannins are added (as mentioned by neutrino, and kno4te) and exceedingly constant every other day 40-50% water changes are done .
I would constantly see older oscars in my area turned in to LFSs with massive scarring, from lack of enough water changing in the high pH tap water.
I also agree with Tlindsey that trying to alter pH is difficult as far as stability goes, and can be problematic.
If you live in an area with constant rain, cutting the tap water with collected rain water can help oscars but unless its constant, your water parameters will bounce up and down.
On another level
And as adults convicts, can get fairly aggressive, much more than oscars, and may rip the oscars to shreds if they choose to. I believe another rough and tumble Central American might be a better tank mate for convicts, even though large and outwardly tough, oscars can be wimps compared to convicts.
Any Central American (like convicts) and Mexican cichlids do well in a pH of 8.4, as would some cichlids from west of the Andes in South America, or all rift lake Africans.
In my experience coming from a place with relatively high tap water pH myself, Oscars usually end up with chronic diseases like HLLE in high pH water, unless tannins are added (as mentioned by neutrino, and kno4te) and exceedingly constant every other day 40-50% water changes are done .
I would constantly see older oscars in my area turned in to LFSs with massive scarring, from lack of enough water changing in the high pH tap water.
I also agree with Tlindsey that trying to alter pH is difficult as far as stability goes, and can be problematic.
If you live in an area with constant rain, cutting the tap water with collected rain water can help oscars but unless its constant, your water parameters will bounce up and down.
On another level
And as adults convicts, can get fairly aggressive, much more than oscars, and may rip the oscars to shreds if they choose to. I believe another rough and tumble Central American might be a better tank mate for convicts, even though large and outwardly tough, oscars can be wimps compared to convicts.
Convict is hard water fish from CA and doesn’t need soft water. Oscar does not need blackwater softness to thrive, but pH 8.4 is rather hard and Oscar is vulnerable to HITH disease. You can buy buffering substrate to soften the water as many shrimp keepers do, but the buffering capacity will use up over time and replacement is expensive for big tank. Mixing with RO water is an alternative, but running the RO unit is slow and tedious, and the unit and renewable membrane aren't cheap. It’s not worth to fight water chemistry for such a big tank as there are many Oscar alternatives that take hard water.
Yikes. Personally, that video would convince me not to mess with it, though, while I didn't use muriatic acid, it's not so different in principle from what I did years ago using mostly aquarist products and extracts-- which is why I say I'd use peat moss if I was doing it today. 
